Multiple short trainings  are meant to cover the entire training, not in one go but it is spread across sessions. These can be short 2 hours or half day sessions. This approach is good when the business users can't allocate continuous time. This works well for users new to BI software; this approach allows the users enough time to practice. The trainings shouldn't have a long gap between two sessions. Long gap breaks the continuity.

Though this approach is difficult if the users are spread across, there could be workarounds, like using online meetings or video-conferencing.